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Background and Purpose Superoxide anions can reduce the bioavailability and actions of endothelium-derived NO. In human resistance-sized arteries, endothelium-dependent vasodilatation can be mediated by H2O2 instead of NO. Here, we tested the hypothesis that in resistance arteries from patients with cardiovascular disease, endothelium-dependent vasodilatation is mediated by a reactive oxygen species and not impaired by oxidative stress. Experimental Approach Small arteries were isolated from biopsies of the parietal pericardium of patients undergoing elective cardiothoracic surgery and were studied using immunohistochemical and organ chamber techniques. Key Results NO synthases 1, 2 and 3, superoxide dismutase 1 and catalase proteins were observed in the microvascular wall. Relaxing responses to bradykinin were endothelium dependent. During submaximal depolarization-induced contraction, bradykinin-mediated relaxations were inhibited by inhibitors of NO synthases (NOS) and soluble guanylyl cyclase (sGC) but not by scavengers of NO or HNO, inhibitors of cyclooxygenases, neuronal NO synthase, superoxide dismutase or catalase, or by exogenous catalase. During contraction stimulated by endothelin-1, these relaxations were not reduced by any of these interventions except DETCA, which caused a small reduction. Conclusion and Implications In resistance arteries from patients with cardiovascular disease, endothelium-dependent relaxations seem not to be mediated by NO, HNO or H2O2, although NOS and sGC can be involved. These vasodilator responses continue during excessive oxidative stress.

One important route of degradation of herbicide pendimethalin in soil leads to formation of non-extractable residues (NER). To investigate NER nature (irreversibly, chemically bound, including possible biogenic NER, or strongly sorbed and entrapped) residues of 14C-labelled pendimethalin in soil were investigated after conventional extraction with organic solvents by silylation. After 400 days of incubation, 32.0% of applied radioactivity (AR) was transformed into NER, 39.9% AR remained extractable. Mineralization reached 26.2% AR. Additionally, 14C-pendimethalin was incubated in soil amended with compost for 217 days to investigate the influence of organic amendments on NER formation. NER amounted to 37.8% AR, with 57.9% AR remaining extractable. Mineralization was negligible (1.4% AR). For all sampling times only low amounts of radioactivity were entrapped (<5% AR) in soil without compost amendment. Pendimethalin was present only in trace amounts (ca. 0.4% AR), other released residues consisted of undefined fractions (sum ≈2% AR). In soil amended with compost, silylation overall resulted in release of higher amounts of radioactivity (19% AR). Addition of compost led to an increase in potential entrapment and sorption sites for pendimethalin, forming higher amounts of strongly sorbed, entrapped residues. Furthermore, potential release of non-extractable pendimethalin residues was investigated by incubation of solvent-extracted soil (without compost amendment) mixed with fresh soil for additional 3 months. NER were partly mineralized (7% AR) and 20% became extractable with organic solvents. However, no pendimethalin or any known metabolites were found.It can be concluded that no parent pendimethalin was found and NER of pendimethalin in soil are mainly formed by covalent binding to organic matrix with only low potential of remobilization under natural conditions.

Lipid bilayers and lipid-associated proteins play crucial roles in biology. As in vivo studies and manipulation are inherently difficult, membrane-mimetic systems are useful for the investigation of lipidic phases, lipid-protein interactions, membrane protein function and membrane structure in vitro. In this work, we describe a route to leverage the programmability of DNA nanotechnology and create DNA-encircled bilayers (DEBs). DEBs are made of multiple copies of an alkylated oligonucleotide hybridized to a single-stranded minicircle, in which up to two alkyl chains per helical turn point to the inside of the toroidal DNA ring. When phospholipids are added, a bilayer is observed to self-assemble within the ring such that the alkyl chains of the oligonucleotides stabilize the hydrophobic rim of the bilayer to prevent formation of vesicles and support thermotropic lipid phase transitions. The DEBs are completely free of protein and can be synthesized from commercially available components using routine equipment. The diameter of DEBs can be varied in a predictable manner. The well-established toolbox from structural DNA nanotechnology, will ultimately enable the rational design of DEBs so that their size, shape or functionalization can be adapted to the specific needs of biophysical investigations of lipidic phases and the properties of membrane proteins embedded into DEB nanoparticle bilayers.

A number of international and national programs classify substances that are persistent (P or very P), bioaccumulative (B or very B), toxic (T), or have the potential for long-range transport. The oldest of these programs is the Stockholm Convention on Persistent Organic Pollutants. More recent programs address persistent, bioaccumulative, and toxic (PBT) properties for chemicals in general (Registration, Evaluation, Authorisation and Restriction of Chemicals, REACH; EC 253/2011) and plant protection products (PPPs) (EC 1107/2009). However, these programs used different criteria for categorization. We critically assessed the criteria and process used in the categorization of PPPs and noted that EC1107/2009, in contrast to the Stockholm Convention or REACH, offers no process for carrying out a further, more refined assessment of those pesticides that are identified as having PBT properties. Thus, in contrast to REACH, few basic screening criteria are used for final-step management decisions. Guidance on the selection of data is not provided, and the criteria used are unclear. For example, no guidance is given as to how the half-lives in soil, water, and sediment should be derived and the term ‘half-life’ is not clearly defined. Large amounts of useful data on environmental and toxicological properties are available for PPPs but most of this is not used in the categorization, for example, photolysis in water, water-sediment, and on soil, important environmental degradation processes particularly relevant to pesticides. The criteria for bioaccumulation and toxicity appear to be focused only on aquatic ecosystems and do not address the terrestrial compartment which is particularly relevant for pesticides and potentially relevant for PBT considerations. The categorization process under EC 1107/2009 could be made more efficient and reduce false negatives and positives if a formal weight of evidence approach was applied to multiple lines of evidence. This paper presents th

Das Hochwasser im Einzugsgebiet der Mulde vom August 2002 hat gezeigt, dass neben der zerstörenden Wirkung des Wassers selbst auch erhebliche Schäden sowie Gefährdungen für Mensch und Umwelt durch die mobilisierten, transportierten und abgelagerten Schadstoffe entstanden sind. Untersuchungen u.a. im vom BMBF geförderten Ad-hocProjekt (FKZ:0330492) belegen dies nachhaltig für urbane Bereiche, beispielsweise für Schwerme-talle, Arsen und PAK. Basierend auf diesen Erkenntnissen war es deshalb notwendig, im Rahmen des Risikomanagements extremer Hochwasserereignisse neben der quantitativen Hydrologie auch die Schadstoffausbreitung zu berücksichtigen.Übergeordnetes Ziel des Projektes war es deshalb, für lokale und regionale Entscheidungsträ-ger ein EDV-gestütztes modellbasiertes Entscheidungshilfesystem zur Schadstoffausbreitung für potentielle Extremhochwasser-Katastrophenfälle zu entwickeln. Dieses Entscheidungshil-fesystem wurde gemeinsam mit dem Landkreis Bitterfeld erarbeitet und implementiert.Das SARISK Projekt wurde im Jahre 2009 abgeschlossen. Es wurde als Verbundprojekt vom Bundesministerium für Forschung und Bildung (PT Forschungszentrum Jülich, FKZ 0330690; VON TÜMPLING ET AL. 2009) innerhalb RIMAX gefördert. Der Endbericht steht unter http://www.ufz.de/data/BTFEnd10676.pdf zum Herunterladen zur Verfügung.In diesem Beitrag wird ein kurzer Überblick zum Projekt gegeben. Die Bereiche hydraulische und Schadstoffausbreitungsmodellierung (Erosion, Transport, Sedimentation) sowie Interak-tion zwischen gelösten und an Partikel gebundenen Stoffen werden ausführlicher dargestellt.Im Februar 2011 kam das System erstmals im Ernstfall zum Einsatz und bewährte sich bei der Hochwasservorhersage.

In recent years several initiatives addressed the inadequate financial support of pollutant-related environmental research in the Federal Republic of Germany. For an objective analysis about the research funding in ecotoxicology and environmental chemistry in Germany, an anonymous online survey was prepared. With support of the Society of Environmental Toxicology and Chemistry (SETAC) - German Language Branch and the German Chemical Society (GDCh) - Division of Environmental Chemistry and Ecotoxicology an invitation to participate in the survey was sent to all members of these two major associations for ecotoxicology and environmental chemistry in Germany (D), Switzerland (CH) and Austria (A). Only senior staff from the areas academics, government and industry was invited. The present article introduces the results of the survey. It is segmented in a section on socio-economic characterization of the participants, a section on support of research by the DFG and a section on funding by other funding organizations. A total of 71 male and female scientists in senior positions from various areas participated in the survey. The results revealed that the participants are to be classified as having excellent records. 48.5% of the respondents had submitted at least one research proposal to the DFG in the past, but one third actually received financial support by the DFG. 64% are not satisfied with the DFG support of pollutant-related research, only 7% are satisfied. It turned out that the research proposals are generally very heterogeneous and thus distributed to various units of the DFG with geosciences, water research and chemistry ranking highest, followed by biology and ecology. 91.2% of the respondents indicated that they have submitted proposals for research funding to other funding institutions (except the DFG), and 83.6% already have received appropriate external funding. 62.3% of the scientists believe that overall support for chemicals-related research in recent ye

Extreme fluvial floods may cause severe contamination with fuel oil and diesel, originating from gasoline pipes and tanks in private households and industrial areas, respectively. Geo-referenced oil spills in the region of Bitterfeld (Germany) after extreme flood events, such as in August 2002, were simulated using the two-dimensional (2D) Finite Element model system Telemac2D, which is subdivided into a hydrodynamic (Telemac-2D) and a transport module (Subief2D). Fuel oil settled via adhesion showed a thickness of less than 1.0 mm. Fuel oil concentrations on the flood wave amounted up to 80 g m-3 in the vicinity of the point sources. At a distance of several hundred meters downstream of the point sources, the fuel oil concentrations were calculated to be zero. Settled areas were only partially contaminated with fuel oil. While one village experienced severe oil contamination, the town of Bitterfeld was almost unaffected by oil spills. It was demonstrated that the 2D transport model applied is capable of simulating fuel oil spills during extreme high waters in the terrestrial environment. Such simulations of fuel oil spills will feed into a GIS-based decision support system of flood protection.

We developed a decision support system (DSS) for sustainable river basin management in the German Elbe catchment (100,000 km2), called Elbe-DSS. The system integrates georeferenced simulation models and related data sets with a user friendly interface and includes a library function. Design and content of the DSS have been developed in close cooperation with end users and stakeholders. The user can evaluate effectiveness of management actions like reforestation, improvement of treatment plant technology or the application of buffer strips under the influence of external constraints on climate, demographic and agro-economic changes to meet water management objectives such as water quality standards and discharge control. The paper (i) describes the conceptual design of the Elbe-DSS, (ii) demonstrates the applicability of the integrated catchment model by running three different management options for phosphate discharge reduction (reforestation, erosion control and ecological-farming) under the assumption of regional climate change based on IPCC scenarios, (iii) evaluates the effectiveness of the management options, and (iv) provides some lessons for the DSS-development in similar settings. The georeferenced approach allows the identification of local inputs in sub-catchments and their impact on the overall water quality, which helps the user to prioritize his management actions in terms of spatial distribution and effectiveness.

Beside damages of infrastructure in industrial regions, extreme floods can cause contamination with particle-bound pollutants, e. g., due to erosion of soils and sediments. In order to predict contamination with inorganic pollutants, the transport and fate of arsenic, lead, and mercury during a fictive flood event of River Vereinigte Mulde in the region of Bitterfeld (Germany) with 200 years recurrence time was modeled. The finite element model system Telemac2D, which is subdivided into a hydrodynamic (Telemac-2D), a transport (Subief-2D), and a water quality module (wq2subief) was applied. The transport and water quality model models were calibrated using results of sediment trap exposures in the floodplain of River Vereinigte Mulde. Model results exhibited that the spatial patterns of particle-associated arsenic and lead concentrations significantly changed. Extended, mostly agriculturally used areas showed arsenic and lead concentrations between 150 and 200 mg kg-1 and 250 and 300 mg kg-1, respectively, while urban areas were to a great extent spared from high contamination with arsenic and lead. Concentrations of particle-associated mercury showed a pattern distinct from those of arsenic and lead. Outside of small patches with concentrations up to 63 mg kg-1, concentrations of particle-associated mercury remained close to zero. Differences in the spatial patterns of the three pollutants regarded mainly arise from significantly different initial and boundary conditions. Sensitivity analyses of initial and boundary conditions revealed a high sensitivity of particle-bound pollutant concentrations, whereas the sensitivities of concentrations of suspended sediments and soluble pollutants were mediocre to negligible.

Applying the two-dimensional model system Telemac2D, the transport of arsenic and oil during extreme flood events was modeled for the region Bitterfeld (Germany). Telemac2D includes sub-routines that describe hydrodynamics, transport and first-order partitioning of soluble and particle-bound pollutants. Oil spills were numerically treated as particulate pollutants with zero settling velocity. Simulations of the inundation of a small region after a dam-break revealed distinct small-scale contamination patterns and partly exhibited severe contamination. Comparison with measurements from the Mulde flood in August 2002 gives reasonable agreement. The model will be calibrated and validated by several measurements with sediment traps during flood events.